Page 606 of 894 NT8D14 Universal Trunk card
553-3001-211 Standard 2.00 September 2004
Jumper strap settings
For most applications, the jumper strap settings remain set to the standard
configuration as shipped from the factory. See Table 185 on page 604.
The jumper strap settings must be changed, as shown in Table 186 on
page 605, for the following:
• For CO/FX/WATS or TIE trunk loops exceeding 1524 meters (5000 ft.)
Table 187
Trunk types – termination impedance and balance network (NT8D14BA, NT8D14BB)
Trunk types
Terminating
impedance
(Note 1)
Balance network for loop lengths (Note 2)
0–915 m
(0–3000 ft)
915–1524 m
(3000–5000 ft)
> 1524 m
(> 5000 ft)
CO/FX/WATS 600 or 900
ohms
600 ohms 3COM 3CM2
2-way TIE (LDR) 600 or 900
ohms
600 ohms 3COM 3CM2
2-way TIE
(OAID)
600 or 900
ohms
600 ohms 3COM 3CM2
DID (loop length
< 600 ohms)
600 or 900
ohms
600 ohms 3COM 3CM2
DID (loop length
Š 600 ohms)
600 or 900
ohms
600 ohms N/A 3CM2
RAN: continuous
operation mode
600 or 900
ohms
600 or 900 ohms N/A N/A
Paging 600 ohms 600 ohms N/A N/A
Note 1: The terminating impedance of each trunk unit is software selectable in LD 14 and
should match the nominal impedance of the connecting equipment.
Note 2: The balance network of each trunk unit is software selectable between resistive 600 or
900 ohms or 3COM and jumper selectable between 3COM and 3CM2. Jumper selection for
3COM/3CM2 restriction does not apply to NT8D14BB.